Hi guys. Just came across this post - lots of interesting ideas and advice on here, thanks!
I've had the same thing this month with the spotting. I've always had brown blood a few days before I start my AF (sometimes with a day's gap in between), but it's a different level this time. Has only been when I wipe, but on and off for last four days. Normally, it gets progressively heavier, darker etc as the days go on. Then I get heavy flow with the fresh blood, first day of my period.
It is really frustrating, as it's so disappointing when you see the signs. This month I'm taking clomid, so not sure when my AF is due but it's normally around CD32. I started the spotting on DPO 6. Have taken a cheap test (evening, minimal amount of wee in cup!), which came back negative, but I'm still 3 days away (if like a normal cycle). Just hate the to and fro guess work and want to move on!
One thing I haven't seen mentioned is your bbt with low progesterone. If you're taking your temps, you normally see it drop off around the time you start to spot (or I do), so it's another sign to help you distinguish IB from any other spotting. The prob with me this month is that my temp dropped, I'd accepted AF as on the way, then it went back up this morning (which could be due to me camping over the weekend). So draining!
Anyway, I'll update on outcome if anybody wants to know what happens. I do have some pregnancy symptoms which could also mean AF (sore boobs, really tired, restless sleep, gassy stomach). Will have to wait and see (where a day feels like a week long episode). I also have a smear test booked in, as I do get cervical erosion from previous hpv treatments. Should check all bases!